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Mammals begin the process of storing up for winter

Red Squirrel.jpg
Red Squirrel.jpg

MammalsBulkingup_091010.mp39.06 MB
Chel Anderson is a botanist and plant ecologist for the Minnesota Department of Natural Resources. She lives here in Cook County and joins us periodically to talk about phenology or what’s going on in the woods right now. Welcome back, Chel.
Anderson: Hello, Jay.
Well, Labor Day has passed, school has started, and I guess we’re officially into fall. That means birds and animals are getting ready for winter. In other words, they’re bulking out.
Anderson: Yeah, they are. I’m sure people hear that word winter and they go, “No, no! Don’t talk about that!” But, I’m going to anyway. So, if anyone like me out there is a gardener, then you know that at this time of year starting already for a month or so and through September and into October, we’re busy putting up food, making things available to us later, you know, when it’s not the growing season anymore. And, even as we’re busy doing that, there are lots of critters, especially mammals, that are doing the exact same thing. The champion species, from my standpoint, in terms of food storage and that would be the red squirrel.
I was going to say chipmunk, but yeah, I won’t argue with you on the red squirrel. Busy, busy.
Anderson: I would say they are champion “cachers,” I’m going to use the word “cache.” They really go about a really concentrated and efficient, comprehensive caching program in the late summer and fall. The kinds of things that they’re working on right now, and it’s really easy to observe, are conifer cones. So, conifer cones and the seeds within them are a key food for red squirrels, and a preferred food. This time of year, if you walk a trail anywhere where there are red squirrels, and that’s most places in our forest, you will find little piles of, or sometimes really big piles, of both cones and just the cone scales. So, the scales of the cone are the hard, kind of woody parts that cover the seeds. Red squirrels, at this point in time, are going around in the tops of the conifers and they’re either cutting with one swift little bite, they’re cutting through the connection between the cone and the twig and letting the cones fall to the ground, or they’re actually cutting the twig. So, on black spruce and white cedar in particular, cones occur in small groups, so they don’t bother trying to get the individual cones, they just cut the twigs, the small twigs, that the cones are attached to and let those fall down, and then they make collections of these on the ground after they’ve spent some time cutting. And then in many cases, they’ll pick a spot, a nice, little perch somewhere, and then they’ll just start working through those cones. They swiftly, unbelievably swiftly, peel back those cone scales and clip out the seed and either eat it or stuff it in their cheek pouches and fill those up. Once they’re full, then they can move them to wherever they’re going to cache the food supply.
So, red squirrels have cheek pouches, but not as big as chipmunks?
Anderson: Right, but they will store those seeds then, along with a variety of other berries, dried berries. Hazelnuts are another important food for squirrels in our area. Good hazelnut crop in many places this year. They peel that green, outer layer off, then they usually put a little bit of a nick in the coat of the seed of the nut. That big husk, they put a little nick in that and then they cache them underground, sometimes by the hundreds to thousands.
Why do they put a nick in them?
Anderson: I think the squirrels put a nick in them, because they dry better, because they want to get at—they’re not going to eat that husk. They want to eat the seed inside. So, the nick seems to be part of, you know, their process of making the seed most edible and it’s part of their process of storing. The dexterity and the efficiency with which they do this, I would say, is equal to the efficiency of grosbeaks on your sunflower seeds. Red squirrels do also collect a lot of fungi. They put them out to dry. So, it’s very common in the woods, you’ll look around up into the canopy of the balsam, and you’ll see these mushrooms just hanging out on the balsam branches, and those have been put there by squirrels. They put them up there to dry, and let them dry. They do a nice job of drying out in the wind, and then they come back and they gather those dry mushrooms and they put them into their caches.
I just realized why it is that I’m fighting an endless battle with red squirrels. They seem to be very bright little creatures.
Anderson: They definitely are.
Chel Anderson, DNR botanist and plant ecologist. Thanks again for helping us understand what’s going on around us this early fall.
Anderson: You’re very welcome.